I'm mining 500 million users, and their "followers" from a social network using their API. The extraction of data itself is not a problem, since I can do it with my scripts. However having 500 million ...

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Thanks for the comments and the help so far. And I apologize for not specifying the question further. I have updated the question below.
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Currently I am asked to develop ...

I have table with observations of objects moving along edges in a graph, this table has the following form:
PK | TIMESTAMP | object_id | from_id | to_id
where object_id is the id of some object and ...